1. Field of the Invention
This invention relates to reels for containing an elongate member wound thereupon, and more particularly to reels for holding a coil of flexible tubing, electrical cable, or the like. It also relates to carriers, such as skids, trucks, trailers, semi-trailers, or the like, for such reels. The invention relates also to methods for supporting such reels on such carriers.
2. Related Art and Information
For many years small pipe strings have been assembled and run into the production tubing or casing of wells, such as oil or gas wells, for such purposes as, for instance, circulating fluids therethrough in order to remove unwanted substances such as water, sand, paraffin, or the like, therefrom. Also, such pipe string was often used in other well operations such as depositing cement, chemicals or other material in the well, displacing liquids with gas, and the like, or for suspending downhole pumps, or the like equipment, or for plugging or fishing operations. Some such operations required that the pipe string make many trips into and out of the well.
Such pipe string was made up of many joints of pipe (each generally 20 to 30 feet in length) connected together by threaded couplings, sometimes called collars. Initially the pipe string was assembled from the individual joints and run into the well, but afterwards could be pulled and re-run two or three joints at a time. Even so, disassembling and re-assembling of the pipe string for each trip, was costly in labor, time, and money.
Reel tubing, also known as coil tubing, has been used for quite a number of years now, and since it is made in lengths which may be thousands of feet long, it can be forced into and pulled from a well under pressure through a stuffing box, and can be moved at several hundred feet per minute, thus greatly speeding up operations and saving much labor, time, and money.
The length of flexible tubing which can be wound upon a reel depends, understandably, upon the outside diameter of the tubing and the dimensions of the reel. Common outside diameters for flexible steel tubing are three-quarter-inch (1.905 centimeters), one-inch (2.54 centimeters), one-and-a-quarter-inch (3.175 centimeters), one-and-a-half-inch (3.810 centimeters), and now two-inch (5,080 centimeters) is available. The rigidity of the flexible steel tubing depends largely upon its outside diameter. Thus, as the outside diameter of the tubing increases, so does the minimum radius to which it may be flexed before it becomes overstressed. Therefore, larger diameter tubing must be wound around large diameter reels. So, in considering two-inch flexible steel tubing having sufficient strength to safely withstand the pressures to be encountered in the usual well servicing operations, the core of the reel must be at least 96 inches (8 feet, or 2.438 meters) in diameter. Then, the reel must have a flange at each end if a worthwhile length of such tubing is to be accommodated. Thus, a suitable reel for two-inch flexible tubing would have flanges about 144 inches (12 feet, or 3.66 meters) in diameter. Larger reels for flexible tubing will minimize bending stresses and thus prolong its useful life. If a 12-foot diameter reel is carried on the bed of a truck, it makes the load too wide if the reel is placed in the usual flat position because 12 feet wide is somewhat wider than is an ordinary highway lane. On the other hand, if the reel is stood on edge, the load becomes too tall to negotiate low overhangs such as underpasses.
There is a need in the oil field for two-inch flexible tubing and 12-foot diameter reels for holding the same. Reels of such size, if patterned after well-known reels, would be overly expensive and excessively heavy.
The same problems may be evident with large reels for electrical cable, hoses, or other elongate members.
Reels, carriers therefor, and methods of supporting them upon their carriers are illustrated and described in the following prior U.S. Pat. Nos.
3,116,781, 3,614,019, 4,071,203, 4,781,250, PA0 3,116,793, 3,658,270, 4,515,220, 4,793,417, PA0 3,559,905, 3,690,136, 4,625,799, 4,799,554,
U.S. Pat. No. 3,116,781 which issued to R. S. Rugeley et al on Jan. 7, 1964 illustrates and describes early apparatus for forcing reeled tubing into a well. A reel 12 contains a coil of tubing. The reel is supported on a support such as a truck bed 11 by a pair of yokes 14 in which the ends of the axle 13 are engaged. The reel 12 is rotatable on its axle 13 to pay out tubing 15.
U.S. Pat. No. 3,116,793 issued also on Jan. 7, 1964 but issued to P. R. McStravick has a drawing which appears identical to that of U.S. Pat. No. 3,116,781 just discussed.
U.S. Pat. No. 3,559,905 which issued on Feb. 2, 1971 to Alexander Palynchuk discloses a reel upon which a sucker rod string is coiled. The reel rotates on an axle or pivot which may be vertical, as seen in FIGS. 1, 10, 11, and 12, or it may be horizontal as seen in FIGS. 13 and 14. The reel of FIGS. 1, 10, 11, 12 can be folded to make it narrow and, therefore quite transportable, see FIG. 10.
U.S. Pat. Nos. 3,614,019; 3,658,270; and 3,690,136 which issued on Oct. 19, 1971; Apr. 25, 1972; and Sept. 12, 1972, respectively, to Damon T. Slator, et al disclose a reel for containing reeled tubing to be injected into a well. The reel R has an axle supported in bearings 15 mounted on the upper end of posts 16, as seen in FIG. 1 of U.S. Pat. No. 3,614,019.
U.S. Pat. No. 4,071,203 which issued on Jan. 31, 1978 to Robert C. Sneed, et al discloses a reel for plastic tubing. The reel 22 (FIGS. 2-3) has an axle supported by the A-frame 34. Thus, the reel is rotatable on its axle.
U.S. Pat. No. 4,515,220 which issued to Phillip S. Sizer, Don C. Cox, and Malcolm N. Council on May 7, 1985 shows, in FIG. 1, a reel of coil tubing 70. The reel obviously pivots about its axle which has its opposite ends supported by a structure resembling an A-frame. Coil tubing 50 is payed out from the reel as the injector 60 forces it into the well 20 and is re-wound upon the reel when the injector withdraws it from the well. (The said Malcolm N. Council is a co-inventor of the present invention.)
U.S. Pat. No. 4,625,799 which issued on Dec. 2, 1986 to William H. McCormick and Charles C. Cobb shows, in FIG. 1, a reel 18 of flexible tubing 17. It appears that the reel pivots on its axle whose ends are supported by upright members attached to a skid which is supported upon the bed of truck 19. Similar showings appear in U.S. Pat. No. 4,781,250 issued to William H. McCormick, Charles C. Cobb, and Malcolm N. Council on Nov. 1, 1989; U.S. Pat. No. 4,793,417 issued to William D. Rumbaugh on Dec. 27, 1988; and U.S. Pat. No. 4,799,554 which issued to Timothy D. Clapp and William H. McCormick on Jan. 24, 1989. (The said William H. McCormick is a co-inventor of the present invention.)
There was not found in the known prior art a reel for tubing, electrical cable, or the like elongate members, having no axle or shaft on which to rotate and which had a hollow drum with a bore therethrough and a gear secured to the reel whereby it could be rotated. Neither was there found a carrier for such a reel having rollers for supporting the reel through engagement of the rollers with the rims of the flanges and having a drive gear for rotating the reel upon the carrier, nor a method for emplacing the same thereon.
The present invention is an improvement over the known reels in that it makes it possible to provide larger reels for containing long sections of elongate members, such as coil tubing, electrical cable, and the like, economically and still be transportable over the highways without exceeding desired height, width, and clearance limitations.